Copolymers of alkenyl diesters of alkenylphosphonic acids with methyl methacrylate



Patented Feb. 14, 1950 UNITED STATES PATENT OFFICE No Drawing. Application April 24, 1946, Serial No. 664,715

9 Claims.

This invention relates to copolymers of alkenyl dlesters of aikenylphosphonic acids with methyl methacrylate.

This application is a continuation, in part, of my co-pending application, Serial No. 625,460, illed October 29. 1945, now Patent No. 2,425,766. issued August 19, 1947. That application describes a process for producing monomeric beta, gamma alkenyl diesters of either allryl or phenyl substituted ethenylphosphonic acids. That process coniprises'reacting beta, gamma unsaturated alcohols with alpha, beta unsaturated alkenyl phosphorus oxydichlorides in the presence of pyridineand then separating the resulting ester from the reaction mass. These esters are liquids which'exhibit little or no tendency to polymerize under ordinary "conditions.

I have "now found that these beta, gamma alkenyl diesters of alkyl and phenyl substituted .ethenylpho'sphonic acids may be copolymerized with methyl methacrylateto produce valuable polymers. 1

The character of the new polymeric compositions may be varied over awide range depending on the polymerizing conditions and the propor 'tions of monomeric starting esters. f

The normally thermoplastic methyl methacrylate resins may be modified to givethermosetting resins of good flame resistance'by copolymerizing monomeric or partially polymerized methyl methacrylate with the alkenylphosphonate monomer in suitable proportions in the presence of catalyst.

The proportions of monomeric esters which eral it is more diillcult to obtain solid type resins when the allrenyl group of the phosphonate is large. For example, when the alkenyl group contains 8 carbon atoms such as in the octenyl and styrylphosphonates, it is preferred to employ a relatively smaller amount of the phosphonate ester if solid resins are desired. On the other hand, with the lower al'senyl groups such as in the butenyl phosphonates. it is possible to readily obtain solid resins in all proportions.

In general the copolymers herein described are produced by mixing the liquid monomeric esters in the desired proportions and dissolving therein .a small amount of the polymerization catalyst, and heatingthe mixture at a temperature below that which will cause decomposition of the start ing esters. The temperature and period of heating will depend on the amount and type of catalyst employed and the degree of polymerization desired.

Suitable catalysts include the organic peroxides such as benzoyl peroxide; acetyl peroxide, tort.- butyl perbenzoate, etc. Benzoyl peroxide is generally preferred because of the ease in controlling the rate of polymerization when such catalyst is used. For example, benzoyl peroxide may be used at temperatures of '70 to 80 C. with satisfactory results whereas a peroxide like tert.-butyl perbenzoate requires a higher temperature and the rate of polymerization is so rapid that carefulcontrol is required to prevent undue decomposition.

The following table illustrates a number of examples of the production of solid resins by copolymerization of methyl methacrylate with a ma'yibe 'employed are not critical though in gennumber of typical alkenylphosphonates.

Methyl Be I Bel cent Methscrylate g' St Polymeriza- Period of Phosphonateiister by Monomer, 7 cc t1on 'lem- Heating, Properties of Polymer Products v Volume Per Cent by peratul'e, C. hours volume monomer) 0 100 0.01 70 20 Water-clear, hard, strong resin. '1 99 0. 01 70 20 D0. 5 95 0.05 70 20 D0. Diallyl isobutenylphosphonata. 10 90 0. 10 70 2) Do. 30 70 0.15 70 20 Do. '50 0. 25 20 Do. 70 0.40 70 20 Light yellow, clear, hard, strong resin. 1 99 0. 01 70 20 Water-white, clear, hard,strong solid. 13 8g 03 '40 20 .%0.

.l 0 '20 0. Dimethallyl isobutenylphos- 30 70 15 70 20 DO. 70 20 Do.

50 50 80 +18 Yellow, clear, hard, strong solid. as 2-3? as 2% em s e saer-w e,cear, r ,srong sol mn ml lyi isooctenylpbos 5 95 n. 05 70 20 D0. P 10 00 0.10 70 20 Do.

i 99 0. 10 70 20 Water-white, hard, strong, solid. Diallylstyrylpliosphonate 5 95 0. 05 70 20 Do.

10 00 0. 10 70 20 Water-white, sl. soft, strong, solid. 5 95 0. 02 70-72 20 Water-white, hard, solid. Dimethallyl isobntenylplios- 10 0.05 70-72 20 Waterwhite, hard, strong solid.

phouate 30 7O 0 12 70-72 20 Do.

80 +18 Faint yellow, hard, strong solid. g 33 n. 02 20 Watg-white, clear, hard, solid.

0. 05 20 0. Diallyl isobutenylphosphonate. 30 70 0 12 70:12 20 +18 Faint yellow, clear, hard, solid. 5 0 02 7072 20 Clear, hard, strong solid. Dimothallyl isooctonylphos- +18 Faint yllow, clear, hard, strong solid.

phonato w m 06 7072 20 Clear, rd, strong solid.

+18 Faint yellow, clear, hard, strong solid.

amuse definite flame-resistance when compared to the normal methyl methacrylate resins.

' The solid copolymers illustrated'above may be produced in the form of shaped articles by poly-- merizing the mixtures in suitable molds. They also may be used in glass and fiber laminates by.

impregnating such fibers with the monomeric or partially polymerized mixtures and then completing the polymerization.

Diallyl and dimethallyl butenylphosphonates and methyl methacrylate will copolymerize in all proportions to form solid type resins; whereas octenyl and styrylphosphonates iorm solid polymers with methyl methacrylate only when the proportion of the phosphonate ester is less than half of the proportion of methyl methacrylate employed. Both the solid and liquid type copolymers are new products and are intended to be within the scope of the present invention.

Liquid copolymers not shown in the above examples may be produced by using higher proportions than shown above of the higher alkenyl phosphonates. For example. an equal volume mixture of methyl methacrylate and diallyl 150-, octenylphosphonate when heated with approximately 2% of benzoyl peroxide at IO-80 C. for hours will produce a viscous liquid product which is suitable for use as a plasticizer in a number of commercial type resins such as cellulose nitrate, ethyl cellulose, vinyl chloride-vinyl acetate copolymers, etc.

Small amounts of the alkenylphosphonate esters when copolymerized with large amounts of methyl methacrylate have a great modifying cf feet on the character of the methyl methacrylate resin. For example, 1% of diallyl isobutenylphosphonate and 99% of methyl methacrylate catalyzed with 0.1% benzoyl peroxide and polymerized 20 hours at C. formed a clear, hard, strong resin which diifered from a straight methyl methacrylate resin. The methyl methacrylate resin was soluble in chloroform, ethylene chloride, a'cetone, benzene, and buty] acetate, whereas the phosphonate-containing copolymer did not dissolve in these solvents, but formed soft gels after 6 days immersion in the solvents at room temperature. Substantially the same difi'erence was observed with copolymers containing 1% dimethallyl styrylphosphonate, and 1% dimethallyl iso-octenylphosphonate. Another difference is in the fact that as little as 1% of the alkenylphosphonate in the copolymer renders the copolymer thermosetting as compared to the thermoplastic character of the straight methyl methacrylate resin.

The foregoing detailed description is given for clearness of understanding only, and no unnec- 4 essarylimitationsshouidbeunderstoodm from, for some modifications will be obvious to thoseskilled'intheart.

.Iclaim:

1.Themethodasset-lorthir claimBinwhicli the catalyst is benzoyl peroxide and the heating isiorasuflicientperiodtoproduceasolidresin product.

2. A solid resin product obtained by 009011? merizing methyl methacrylate and a di beta,-v

gamma alkenyl iso-octenylpte in the proportions of from 2 to 99 volumes of methyl methacrylate to one volume'oi'the iso-octenylphosphonate ester.

3. A copolymer obtained bycopolymerizing 30' to 99% by volume of methyl methacrylate and 70 to 1%. by volume of a beta, gamma alkenyl diester of an alkenylphosphonic acid selected from the class consisting of alkyl and phenyl substituted ethenylphosphonic acids.

- 4. A solid resin product comprising a copoiy-, mer obtained by copolymerizing about 30 to 95% by volume of methyl methacrylate and 70 to 5% or a di beta, gamma alkenyl isobutenylphoaphonate.

5. The method of forming a thermosetting methyl methacrylate resin which comprises reacting from 30 to 99% by volume of thermoplastic methyl methacrylate with 70 to 1% by volume of a beta, gamma alkenyl diester of an alkenylphosphonic acid selected from the class consisting of alkyl and phenyl substituted ethenylphosphonic acids in the presence of an organic peroxide polymerization catalyst and at about 70 to C. for a period or time sumcient to form a thermosetting resin.

6. A method which comprises reacting from 30 to 99% by volume of methyl methacrylate with 70 to 1% by volume or a beta, gamma alkenyl diester of an alkenylphosphonic acid selected-from the class consisting of alkyl and phenyl substituted ethenylphosphonic acids in the presence of an organic peroxide polymerization catalyst at .about 70 to 80 C. for a period of time suiiicient to form a copolymer.

No references cited. 

6. A METHOD WHICH COMPRISES REACTING FROM 30 TO 99% BY VOLUME OF METHYL METHACRYLATE WITH 70 TO 1% BY VOLUME OF A BETA, GAMMA ALKENYL DIESTER OF AN ALKENYLPHOSPHONIC ACID SELECTED FROM THE CLASS CONSISTING OF ALKYL AND PHENYL SUBSTITUTED ENTHENYLPHOSPHONIC ACIDS IN THE PRESENCE OF AN ORGANIC PEROXIDE POLYMERIZATION CATALYST AT ABOUT 70 TO 80*C. FOR A PERIOD OF TIME SUFFICIENT TO FORM A COPOLYMER. 